Here is the patent of USDA with US 6,399,800.
In summary, In this patent , Biodiesel Process from Soapstocks.
a- saponifying a SS with alkali to form a saponified (hydrolyzed) feedstock
b) removing water from saponified feedstock to form a dried saponfied feedstock containing no more than about 10% water,
c) esterifying the dried saponified feedstock with an alcohol and inorganic acid catalyst to form FATTY ACID ALKLY ESTER and
d) recovering the fatty acid alkly ester

There is an important clues and differences between patended works and new article ( I think that has not been still patent registration)
But Michael's other article sent me
Process stages of Biodiesel from Soapstock was determined as described below.
a)saponificaton
b) (*) acidulation- that is differences point
c)esterifying with acid catalyst and an alcohol
d) base stage
at patented works, Molar ratios for esterifiying (FFA:Alcohol: H2SO4: 1/30/2,5)
At his article, http://biodiesel.infopop.cc/eve/forums/a/tpc/f/629605551/m/4801081961
Molar ratios for esterifiying (FFA:Alcohol: H2SO4: 1/1,8/0,17
there is obviously huge cost reduction.
Submmited to your knowledge
regards